Street sweeper hopper and lift mechanism



Dec. 22, 1959 H. BURGDORFF STREET SWEEPER HOPPER AND LIFT MECHANISMFiled March 8. 1956 4 Sheets-Sheet 1 wmrm SY .NNW

BY gw W 4 Trae/vf ys.

Dec. 22, 1959 -H BURGDQRFF 2,917,761

STREET SWEEPER `HOPPEIR AND LIFT MECHANISM Filed March 8, 1956 V 4Sheets-Sheet 2 /04 llll f INVENTOR.`

H. BURGDORFF Dm, 2z, 1959 STREET SWEEPER HOPPER AND LIFT MECHANISM FiledMarch 8, 1956 4 Sheets-Sheet 3 mw M 0 N 1 i YM Bf Dec. 22, 1959 H.BURGDORFF STREET SWEEPER .HOPPER AND LIFT MECHANISM Filed March 8, 19564 sheets-Sheet 4 nited States Patent STREET SWEEPER HOPPER AND LIFTMECHANISM Henry Burgdorft, Long Beach, Calif.

Application March 8, 1956, Serial No. 570,293

9 Claims. (Cl. 1S-84) This invention relates generally to modern motordriven street sweepers and more particularly to an improved sweeperwhich greatly facilitates dumping of the refuse gathered therein.

In the conventional street sweeper regardless of its arrangement it iscustomary to provide a pick-up broom which extends across the path ofthe sweeper and pushes dirt and refuse towards a refuse-receiving hopperwherein it is temporarily stored. Usually a conveyor or elevator isprovided for carrying the refuse into the hopper from the pick-up broom.Side gutter brooms for sweeping refuse out of the street curbings andinto the path of the pick-up broom are also provided, as may be waterspraying nozzles and other accessories.

As can be appreciated, the refuse gathered in the hopper must beperiodically and rather frequently emptied out, and ultimately taken toa city dump or other disposal area. It is with this problem that thepresent invention is principally concerned. In prior devices of thiskind, the dirt or refuse-receiving hopper is mounted between the frontand rear wheels of the sweeper and is equipped with bottom opening dumpgates which normally cover a downwardly directed discharge openingdisposed longitudinally between the front and rear wheels. When the dumpgates are opened the refuse in the hopper is deposited in a pile beneaththe sweeper. After the sweeper has been driven away the pile of refuseis subsequently gathered into a dump truck or other conveyance in whichit is taken to the ultimate disposal area.

It is obviously of great advantage if the refuse stored inthe sweepercan be discharged or dumped from the end of the sweeper rather than froma middle position between the wheels. By the use of end dumping thesweeper can be driven to the edge of a pit or loading dock anddischarged directly therein rather than the requiring subsequenthandling, reloading and redumping. However, this has not heretofore beenachieved because the position of the pick-up broom and lift elevatorrelative to the refuse hopper is such as to normally interfere with anyattempted end dumping arrangement.

With the foregoing in mind, it is therefore a major object of theinvention to provide a modern type street sweeper having means fordumping refuse from the end of the sweeper rather than from a positionbetween the wheels thereof. l

An equally important object of the invention is to provide a streetsweeper of the character described in which the pick-up broom and liftelevator are moved out of the discharge path of the refuse when thehopper dump gate is opened.

It is another object of the invention to provide a street sweeper havinga refuse hopper provided with a lower discharge opening positionedlongitudinally outwardly of the wheels and a pivotally movable dump gatemounted thereon.

A further object of the invention is to provide a street sweeper havinga pivotally mounted dump gate and means associated with the gate and anadjacent elevator ICC and broom for opening the gate and moving theelevator and broom out of the discharge path of the hopper.

It is also an object of the invention to provide a dump gate havingsupplemental storage volume therein and arranged to be emptied when saidgate is moved to an open position, the release of refuse from said gatealso acting to loosen the refuse within said hopper and expedite thedumping thereof.

Still another object of the invention is to provide force-applying andlinkage means operable to move said gate, elevator and broom to open andcleared positions and to permit independent lifting of the elevator andbroom.

A still further object of the invention is: to provide a. gate havingself-latching means actuated for release by the operation of the openingand lifting means.

Yet another object of the invention is to provide a street sweeper ofthe character described which is of simple and durable construction forwithstanding rugged use.

These and other objects and advantages of the inven tion will becomeapparent from the following detailed description of a preferred formthereof, and from an inspection of the accompanying drawings in which:

Figure 1 is a side elevation of a preferred embodiment of the streetsweeper in operating position;

Figure 2 is a cross sectional detail taken along the line 2-2 of Figure1;

Figure 3 is a cross sectional detail taken along the line 3 3 of Figure1;

Figure 4 is an elevational detatil partially broken awayto show theinterior elevator and hopper construction;

Figure 5 is an elevational detail showing the elevator and broom liftedfor road traveling operation;

Figure 6 is an opposite side elevation detail;

Figure 7 is an elevational detail similar to Figure 6 showing theelevator and broom lifted clear of the refuse discharge path and the`hopper gate opened; I igure 8 is a schematic of the hydraulic controlsystem; an

Figure 9 is a detail of the hopper gate latch mechanism.

Referring now to the drawings and particularly to Figure 1 thereof, theinvention is disclosed in conjunction with a motor-driven street sweeperof the four-wheeled type. The sweeper has a longitudinally extendingframe designated generally at 20 and is provided with a pair of rearsupporting Wheels 21 and front steerable wheels 22. In this instance,the front portion of 'the sweeper is arranged similar to a conventionalmotor truck and includes an engine (not shown) which is used to drivethe sweeper and operate the various parts of the sweeper assembly.Behind a front hood 23 and fenders 24 is an operators cab 25 containinga steering wheel 26 and various controls, for operating the sweeper, anddriving the vehicle along the street. A water spray pipe 27 is alsomounted at the front of hood 23 and sends a spray downwardly in front ofthe path of the sweeper to prevent the raising of dust by the sweepingoperation.

Behind the cab 25 is a large body 30 which is supported on frame 20above the rear wheels 21 and together with the other relativelystationary parts may be designated as the sweeper body assembly. Mountedat the side of the sweeper between the front and rear wheels isa largecircular broom 31 which is driven for rotation about a generallyvertical axis and. makes sweep ing contact with the surface of thestreet beneath the sweeper and to the side thereof as would be adjacentthe curbing of a conventional street. Broom 31is termed the gutter broomand functions to sweep dirt out of the curbing gutter and laterallyinwardly to a position beneath the sweeper.

Extended transversely across the sweeper at therrear end thereof is alarge cylindrical pick-up broom 32 which is supported for rotation aboutits horizontal axis. As will later be described, pick-up broom 32 isdriven for forward and upward rotation so that it sweeps refuse upwardlyto clean the pathway of the sweeper. This includes the refuse normallylying within the wheel track; of 'the sweeper as well as the refusethrown outwardly from the curbing by the gutter broom 3i. Mountedbetween the body assembly 30 and the pick-up broom 32 is an elevatorassembly 35 which is adapted to receive refuse fromV broom 32 and carryit forward and. upwardly into a refuse hopper 36 which is containedwithin body 30. Subsequently, when refuse hopper 36 is fullV it. may bedumped to complete the sweeping cycle. While this. serves in a generalway to describe the operation of the sweeper, the interrelation ofthevarious parts can best be understood by considering the structure inmore detail.

p The frame 20 comprises two spaced parallel elongated channels whichare connected to the framework of the vehicle under cab 25 and extendrearwardly and slightly upwardly to the end of sweeper body 30. The bodyassembly 30 is a large box-like housing which includes the lrefusehopper 36 and a forward water tank 3? adjacent the bottom of cab 25'.vThe structure includes vertical side panels or walls 40 which aresupported just inside frame channels 20 and extend upwardly aconsiderable distance. The shape of walls 46 is rectangular along thefront and top edges, upwardly and forwardly sloping along the rear edge,and somewhat irregular along the bottom. A front wall `41 joins sidewalls 40 together and serves as the rear partition of cab 25. A rearwall 42 extends only partially up the sloped back edge and the topportion thereof is open t`o define an intake opening 43, as is best seenin Figure 4, for receiving refuse within the hopper 36.

The forward bottom portion of the refuse hopper 36 is id'eiine'd by atransverse sloping partition 44 which extends 'forwardly and upwardlyfrom a point spaced above rear wheels .V21 to approximately the middleof forwardwall 41. Partition 44 also forms the top of water tank 37, theremainder of the tank being formed b`y downwardly convergent bottomwalls 45 and 46 which join with the top Wall and front wall 41,respectively.y The position of water tank 37 is quite desirable"since/ift is supported' between the sweeper wheels and also has a lowcenter of gravity for good weight distribution.

As thus far defined it can be seen that refuse hopper 36 has the rearupper' intake opening 43 and a rearwardly sloping front portion which is'open downwardly from a point above rear wheels 21 to the partial rearWall A42. A top wall 48 may extend over the entire hopper` and be formedwith an access hatch 49 therein forcleaning purposes. In order tofacilitate dumping of hopper 36 a rear tail or chute portion is extendeddownwardlyrtherefrom behind rear wheels 21 and, as is best seen inFigure 4, is formed by a steeply angled bottom wall 50 joined with theforward bottom partition 44 land extended downwardly to a rearwardly anddownwardly facing discharge opening 51 which lies between the end ofwall 56 and rear wall 42. The sides 40are extended downwardly to coverthis chute portion and have two angularly intersecting edge sectionsadjacent t'o discharge opening 51, a front'section 52 extendinglrearwardly "and upwardly from the corner of bottom wall 50,`and a rear'section 53 intersecting therewith and' extending approximately'vertically upwardly therefromv to` thelower corner of rear wall v42. InAother w'ords, from the side, the discharge opening l51 has the upperrearcornerthereof cut VVhack 'along the vertical .edge section. 53.

` Discharge opening 51 is normally closed to permit the accumulation ofrefuse in hopper 36, and this is accomplished by means of a dump gate 56which is formed as a bucket-like cover which itself provides storagevolume for refuse. Gate 56 has a rear wall 57 joined to a horizontallyextending bottom Wall 58 lying some distance below discharge opening 51but extending forwardly to meet the rear corner of bottom wall 50. Rearwall 57 extends along the aforementioned vertical edge section 53 ofopening 51 to make a tight closure therewith. ntriangular side walls 59are tted within walls 57 and 55 and shaped to fit tightly with the frontedge sections 52 of walls 40 to complete the closure of the dischargeopening 51. As can thus be seen, gate 56 deiines a supplementalcontainer extending the storage capacity of hopper 36.

The entire gate assembly 56 just described is pivotally connected torear wall 42 by a horizontal hinge 60 extended across the lower edge ofthe rear wall, as is best seen in Figure 3, and the gate is thus adaptedto swing rearwardly from its normal closed position to a position spacedfrom discharge opening 51 with an action as is best seen in Figures 6and 7. it will be noted that discharge opening 51 is behind rear wheels2l.v and that when gate 56 is opened the refuse within hopper 36 has astraight and clear discharge path. It can also be appreciatedl that themovement of the dump gate 56 tends to cause a freeing of the refusewithin the hopper since part of the refuse moves with the gate and asuddent dislodging action takes place. When opened, gate 56 is in effectupturned, and any refuse riding therein is simultaneously dumped freeand clear.

While the action of gate 56 is one of the important features of theinvention, its cooperative relationship with the remainder of thesweeper assembly is also portant and requires a description of the.remaining elements. This is particularly true of the elevator and broommechanisms which move with the gate in the dumping operation. v

As was previously mentioned, the pick-up broom 3 2 is mounted at therear of the sweeper. Broom 32 1s supported ona pair of arms 64 which arepivotally connected to frame channels 20 at their forward end and extenddownwardly and rearwardly for floating or pivotal action in a verticalplane. At the ends of arms 64 are bearing plates 65 containing bearings66 which rotatably support a broom shaft 67 that forms a part ofa broomcore 68, Vas is best seen in Figure 4. The broom 32 may be, in and ofitself conventional, and comprises bristles 63 mounted on core 68 in acylindrical overall shape.

Mounted at the left hand end of broom 32 is a hydraulic drive motor 70which is supported on the left arm 64 and is free for pivotal movementwith the arm. Motor 70 is suitably connected to broom shaft 67V andserves to rotate broom 32 forwardly and upwardly in a counterclockwisedirection4 as viewed in Figures l and 4. The action of bristles 69V is.thus to sweep refuse Vforwardly and upwardly as :broom 32 traverses thestreet. The purpose ofrhaving arm 64 pivotally mounted is to permitbroom-32 to ride along the surface of .thestreet in conformance to thecontour thereof for sweeping contact. It is also to permit the raisingof broom 32 off the street for road traveling purposes as willsubsequently be described in connection with the operation of theelevatorassembly. l Y

In order to -adjust the weight or tension withwhich broom 32 rides onthe street adjustable spring supporting means forfarms 64 are provided.These springsupporting means take the'form of -a pair ofelongatedcoilsprings 72 which are connected at Vtheir upper ends to upstganding'standards 73 that are rigidly supported on `.the ends of both framechannels 20. The lower l'ends of springs`72 areconnected to adjustmentnuts 74 which4 are threadedly 'engaged on 'adjusting screws 75.Thelatter are rotatably mounted -on :arms -64 by brackets76 and havevfront handles 77 by which they may be rotated. As screws i5 are rotatedthe position of nuts 74 relative thereto is moved to change theeffective length of supporting springs 72. For normal usage, springs 72are adjusted so that they substantially balance the weight of broom 32and its supporting structure.

The previously mentioned forward gutter broom 31 is supported in agenerally similar manner to the rear broom 32. The basic support forbroom 31 is provided by an arm 30 which is pivotally supported on theright hand frame by a bracket 31 at a point above the rear wheel 21, andextends forwardly and connects right angularly to a downturned arm S2.Broom 31 has an upper support disc 33 to which are secured downwardlyprojecting bristles 84. Disc 83 is supported on the end of a rotatabledrive shaft 85 which extends upwardly through support arm 82 and isjournaled therein. Mounted at the top of arm 82 is a hydraulic drivemotor 87 which is suitably connected to shaft 85 to rotate it, and linturn, broom 31.

When the sweeper is traveling to and from sweeping locations it isdesirable to lift broom 31 free of the road surface. To this end, apivotally mounted crank 90 is supported on frame 20 midway of the lengthof arm by a pivot pin 91 connected near the lower end of the crank. Theupper end of crank 90 carries a roller 92 which passes under arm 80 insupporting relationship. A hydraulic ram 93 is connected between crank90 and a fixed point on bracket 81 and is adapted for extension andretraction in the usual manner. As shown in Figure 1, ram 93 is in theextended position causing crank 90 to be rotated forwardly anddownwardly so that broom 31 engages the street surface. When it isdesired to lift broom 31, ram 93 is retracted and crank 90 is pivotedupwardly to the position shown in Figure 5.

In order to prevent the full weight of gutter broom 31 from resting onthe ground, an adjustable spring-supporting means is connected betweencrank 90 `and body assembly 30 and tends to pull the crank upwardly. Oneend of a coil spring 95 is connected to bracket 81 and the other endconnects to an adjusting nut 96 carried on an adjusting screw 97 whichextends parallel to crank 90 and is supported thereon. A handle 98 isprovided on the end of screw 97 and by rotating the screw the positionof nut 96 may be changed to adjust the tension on spring 95. Again, theusual adjustment of spring 95 is such that it supports substantially allof the weight of broom 31 and the latter exerts only a light sweepingpressure.

The elevator assembly which is positioned between rear broom 32 andrefuse hopper 36 is formed with two vertical walls or side plates 102which extend downwardly from the top of the hopper to a point spaced ashort distance above the ground level. spacing of plates 102 is slightlyless than that of body side walls so that the plates lie just inside ofthe latter. Extended across between the front edge of plates 102 is anelevator bottom wall 103, which, as is best seen in Figure 4, extendsparallel to rear hopper wall 42 from its top to a point near the bottomof the elevator. The lower edge portion of wall 103 may be curvedrearwardly and upwardly. Above rear wall 42 the side plates 102 projectforwardly a short distance and lap the inside of hopper side walls 40within the previously mentioned hopper intake opening 43.

The rear edges of side plates 102 curve rearwardly from the top frontcorner and then slope downwardly at a flatter angle to a point above andjust to the front of rear broom 32. From this point the rear edges curveupwardly over the broom, angle downwardly and return forwardly toprovide rear skirts 104, and then curve downwardly to join the frontedges at a rounded bottom portion, as is shown in Figure 4. The externalframework of the elevatorassembly is completed by a trans- The lateral tversely extending xed top cover 105 secured alongthe upper rear edges ofthe side plates, and a lower hinged fender 106 which is secured to theupper cover by a` transverse hinge 107. Fender 106 continues rearwardlyalong the top of skirt portions 104 to cover broom 32, and is pivotallymovable upwardly for cleaning and repair ofthe broom. t

Within the elevator assembly 35 are means movable to carry refuseupwardly from broom 32 to refuse hopper 36 in the form of a conveyorhaving an upper drive shaft 110 extended transversely across betweenplates 102. Outboard of left hand side plate 102 (Figure 6) is ahydraulic motor 111 suitably connected to rotate shaft 110 in acounterclockwise direction as viewed in Figure 4. Inside of theelevator, shaft 110 carries spaced drive sprockets 112 which engage withconveyor chains 113. The latter extend downwardly parallel to the hopperbottom 103 and are rotatably supported at their lower ends on idlersprockets 114 which are carried on a lower shaft 115. Conveyor chains113 move counterclockwise around the path established by sprockets 112and 114, and support transversely extending lift or squeegee bars 116which are spaced apart on the chains and are of such a size that theyslide closely along elevator bottom 103 when on the lower half of theirpath. As lift bars 116 move upwardly along elevator bottom 103 they liftthe refuse upwardly until the hopper intake opening 43 is reached. Atthis point the refuse falls forwardly into hopper 36, and the bars 116turn upwardly over upper sprockets 112 and return downwardly to thebottom of the elevator.

In order to confine the refuse against spreading laterally outwardly asit is swept up by broom 312, side drag shoes 120 are mounted at thelower ends of the elevator side plates 102. The drag shoes 120 havelower skids 121 which slide along the surface of the street so that theyprovide a protective closure along the sides of broom 32 and forwardlyup to the bottom elevator wall 103. Shoes 120 are connected to sideplates 102 by means of pins 123 extended from the plates and engagedwithin elongated vertical slots 124 formed inthe shoes. This connectionpermits the shoes 120 to conform to the surface irregularity in thestreet without disturbing the position ofthe elevator.

When the sweeper is to be driven to and `from sweeping jobs it isdesirable to elevate broom 32 and shoes 120 clear of the ground from thenormal sweeping position to that shown in Figure 5. For this purpose ahydraulic ram 125 is mounted upon the right hand side plates 102. Theupper end of ram 125 is pivotally connected to the side plate 102 andthe lower end is connected to a pivotal crank 126 which is mounted on across shaft 127 extended between the side plates and rotatably journaledtherein. The left hand end of shaft 127 carries a crank arm 128 similarto crank 126, and both are thus adapted to be moved pivotally uponextension or retraction of ram 125.

On both sides of the sweeper the cranks 126 and 128 are connected byflexible chains 130 with the broom supporting arms 64 and the shoes 120.Normally, ram 125 is extended, and cranks 126 and 128 are turnedrearwardly and downwardly so that both broom 32 and shoes 120 are freeto ride on the street surface. When ram 125 is retracted, as shown inFigure 5, chains 130 act to lift the arms 64 and shoes 120 so that thelatter and broom 32 are clear of the street. In this position, and withthe forward gutter broom 31 elevated as has been previously described,the street sweeper has normal truck characteristics Vand can be drivenrapidly to and from the sweeping locations. It should also be noted thatthe chain connections 130 permit complete freedom of movement of broom32 and shoes 120 when in the sweeping position for conformance withstreet irregularities.

The complete elevator assembly 35 thus described, is pivotally supportedon the rear wall 42 of the refuse hopper 36. As is best seen in Figure4, a hinge 135 is extended along the top of wall 42 and is connected tothe elevator bottom wall 103. This connection allows elevator assembly35 to pivot upwardly from its normal position to the position shown inFigure 7. As this occurs, the upper leading edge portions of side plates102 slide freely forwardly into hopper 36. As elevator assembly 35 movesupwardly the broom 32 and shoes 120 are also lifted through theconnection of lifting chains 130 and cranks 126 and 128.

Lifting of elevator assembly 35 is accomplished by means of a pair ofhydraulic rams 137 which are connected between body assembly 30 and theelevator assembly. The front ends of rams 137 are pivotally connected tothe hopper chute portionV of side walls 40 just above hopper gate 56,and the rear ends of the rams are elevated slightly and pivotallyconnected to elevator side plates 102 at points spaced above shoes 120.Normally, rams 137 are in a retracted position as shown in Figures l and6. When the rams 137 are extended they force the bottom portion ofelevator assembly 35 to move rearwardly and upwardly to the positionshown in Figure 7. The purpose of lifting elevator assembly 35 is tomove it free and clear of the discharge path of the refuse when hoppergate 56 is opened. Also, since the elevator assembly 35 is lifted thesweeper can be more readily backed up to a dumping site.

As will be remembered, in order to dump the refuse from hopper 36 thelower dump gate 56 is opened by pivoting it rearwardly. This isaccomplished at the same time that elevator assembly 35 is lifted bymeans of a connection between assembly 35 and gate 56 in the form oflinking levers 140. The upper ends of levers 140 are threaded andadjustably connected to` brackets 141 mounted on elevator side plates102 by nuts 142. Levers 140 angle forwardly and downwardly and the lowerends are connected to latches 144 which are mounted on the side plates59 of gate 56.

Each latch 144 is pivotally secured to side plate 5% by a pin 145 whichextends through a small box-like housing 146 mounted thereon as is bestseen in the detail of Figure 9. The upper and lower edges of housing 146limit the pivotal movement of the lever and a small spring 147 confinedtherein urges the forward end of the latch upwardly. On the leading endof latch 144 is a hook end 148 which is adapted to engage a fixed keeperplate 149 mounted on hopper side wall 40. Hook 148 has a tapered leadingedge 150 and is adapted to be self-latching with keeper plate 149 whengate 56 is closed.

When elevator assembly 35 is lifted upwardly by hydraulic rams 137 thelinkage levers 140 act to first pull the rear end of latches 144upwardly against the urging of springs 147 to release hooks 148 fromkeeper 149. This frees gate 56, and continued movement of levers 140pulls the gate rearwardly and upwardly to the open position shown inFigure 7. As can thus be seen,v the elevator assembly 35 and hopper gate56 move simultaneously to an open position to provide a free path forthe discharge of refuse. Rear broom 32 is, of course, moved out of thepath of the discharging refuse through its connection with elevatorassembly 35. When refuse hopper 36 is emptied, the hydraulic pressure onrams 137 is released, and the weight of elevator assembly 35 causes itto pivot downwardly to its normal position. Gate 56 is automaticallyclosed through the actio'n of latches 144 and the sweeper is ready forcontinued `sweeping operation.

Figure 8 shows a schematic diagram of the system for the varioushydraulic operating elements which have previously been described. Inaddition to the described elements, the system includes hydraulic fluidstorage tank 154 anda hydraulic system pump 155, the latter beingadapted for connection to' the sweeper engine by suitable means such asa drive belt 156. From pump 155 the .hydraulic fluid under pressure isconducted through suitable lines to a set of control valves which areused to control the operation of the hydraulic rams and drive motors.Three such valves are illustrated, these being a control valve which isused for operating the gutter broom motor 87 and gutter broom ramcylinder 93, a Valve 161 for the rear broom motor 70 and rear broomlifting ram cylinder 125, and a valve 162 for the elevator lifting ramcylinder 137 and elevator motor 111. Each of the control valves is ofconventional multiple port construction so that the various operatingelements can be driven at high or low speeds and in opposite directions.it should be noted that the lines used to connect the control valveswith the operating elements are of fiexible hose type. Thus, themovement of the various parts previously described in the operation ofthe sweeper is not hampered in any way by the hydraulic connections.

While I have thus described in considerable detail a preferredembodiment of the invention, it is to be understood that modification ofdesign and construction can be made without departing from the scope o'fthe invention. Therefore, l do not wish to be limited to the foregoingexcept as defined in the appended claims.

I claim:

1. A street sweeper which includes: a body assembly including arefuse-receiving hopper; a pick-up broom extending across said sweeperand connected to said body assembly fo'r limited vertical movement; anelevator mounted between said broom and said hopper and having means forcarrying refuse from said broom to said hopper, said elevator beingsupported for limited vertical movement relative to said body assembly;means connecting said broom and elevator to limit lifting of said broomindependently of said elevator to a transporting position of said broomand adapted to lift said broom in response to lifting of said elevator;a dump gate mounted on said assembly at the bottom of said hopper andmovable from a normally closed to an open position; means connectingsaid gate and elevator adapted to open said gate in respo'nse to liftingof said elevator and means connected to said body assembly for movingsaid broom and said elevator upwardly and clear of the discharge path ofsaid refuse.

2. A street sweeper which includes: a body assembly including arefuse-receiving hopper; a set of supporting wheels mounted on said bodyassembly; a pick-up broom extending across one end of said sweeper andconnected to said body assembly for vertical pivotal movement; anelevator mounted between said hopper and said broom and having meansmovable to lift refuse upwardly into said hopper, said elevator beingpivotally connected to' said body assembly for vertical movement; forceapplying means interconnecting said broom and elevator to move saidbroom between sweeping and transporting positions thereof when saidelevator occupies a lowered position and adapted to lift said broomupwardly beyond transporting position when said elevator is lifted; adump gate mounted on said assembly at the bottom of said hopper andmovable fro'm a normally closed to an open position, said gate beingpositioned longitudinally outwardly of said wheels adjacent saidelevator; means connecting said gate with said elevator; andforce-applying means connected to said body assembly and said elevatorfor pivotally lifting said elevator and said broom out of the dischargepath of said refuse and opening said gate.

3. A street sweeper which includes: a body assembly including arefuse-receiving hopper having an upper in- -take opening and a lowerdischarge opening; a set of supporting wheels mounted on said bodyassembly longitudinally inwardly of the discharge opentng on saidhopper; a pick-up bro'orn extending across one end of said sweeper andconnected to said body assembly for vertical pivotal movement; anelevator mounted between said broom and said hopper and Vhaving meansmovable to lift refuse upwardly into said hopper, said elevator beingCODQGCed O .Said bOdy assembly for vertical pivotal 9 movement; a dumpgate mounted on said assembly at the discharge opening of said hopperand pivotally supported for movement from a closed position to an open`position spaced from said opening in the direction of said elevator;latch means normally holding said gate closed; means connecting saidbroom to said elevator for movement with said elevator and allowing saidbroom to lift between sweeping and transporting positions thereofindependently of said elevator; force applying means connected to saidbroom for moving said broom between sweeping and transporting positions;means operatively associated with said latch means and connecting saidgate with said elevator; and force-applying means connected to said bodyassembly and said elevator for pivotally lifting said elevator and saidbro'om out of the discharge path of said refuse and opening said gate.

4. A street sweeper which includes: a body assembly including arefuse-receiving hopper having an upper intake opening and a lowerdischarge opening; a set of supporting wheels mounted on said bodyassembly longitudinally inwardly of the discharge opening on saidhopper; a pick-up broo'm extending across one end of said sweeper andconnected to said body assembly for vertical pivotal movement; anelevator mounted between said broom and said hopper and having meansmovable to lift refuse upwardly into said hopper, said elevato'r beingconnected to said body assembly for vertical pivotal movement; a dumpgate mounted on said assembly at the discharge opening of said hopperand pivotally supported for movement from a closed position to an openposition spaced from said opening in the direction of said elevator;self-latching means holding said gate in said closed position; meansconnecting said broom to said elevator fo'r vertical movement of saidbroom with said elevator, and limiting said broom to movement betweensweeping and transporting positions thereof independently of movement ofsaid elevator when said elevator is in a lowered position; meansconnected between said latching means and said elevator for opening saidlatching means and moving said gate to said open position when saidelevator moves upwardly; and force-applying means connected to said bodyassembly and said elevator for pivotally lifting said elevator and saidbroom out of the discharge path o'f said refuse and opening said gate.

5. A street sweeper which includes: a body assembly including arefuse-receiving hopper having an upper intake opening and a lowerdischarge opening; a set of supporting wheels mounted on said bodyassembly longitudinally inwardly of the discharge opening on saidhopper; a rear pick-up broom extending across said sweeper; a pair ofsupporting arms attached to said broom and extending forwardly andupwardly, said arms being pivotally connected to said body assembly;means for rotating said broom forwardly and upwardly; an elevatormounted between said broom and said hopper, the lower end of saidelevator being positioned to receive refuse from said broom uponrotation of the latter, said elevator having lift means therein movableto lift refuse up to the upper opening of said hopper and said elevatorbeing pivotally connected to' said hopper for upward and rearwardpivotal movement; means interconnecting said elevator and broom forsupporting said broom in a lowered sweeping position and a raisedtransporting position independently of said elevato'r, and adapted tolift said broom during upward pivotal movement of said elevator; a dumpgate positioned over the discharge opening of said hopper and having anangular bucket shape forming an extension of said hopper, said gatebeinev pivotally mounted to said hopper at the rear end of said openingfor rearward pivotal movement, said gate being normally closed andmovable rearwardly to an inverted position for the discharge of refusefrom said hopper and said gate; self-latching means holding said gate insaid closed position; means connected between said latching means andsaid elevator for opening said latching means and moving said gate tosaid open position when said elevator moves upwardly; and afluid-actuated plunger connected to said body assembly and said elevatorfor lifting said elevator and said bro'om out of the discharge path ofsaid refuse and opening said gate.

6. In a street sweeper vehicle having a refuse receiving hopper, a dumpgate spaced rearwardly of the supporting wheels of said vehicle forclosing a discharge opening formed in said hopper, a verticallyswingable pick-up broom assembly at the rear end of said vehicle, andanelevator assembly pivotally mounted on said hopper and positionedbetween said broom and said hopper to conduct refuse from said broomupwardly into said hopper, the improvement comprising the combinationo'f: force applying means interconnecting said broom assembly and saidelevator assembly that is operable to move said broom. assembly betweentransporting and sweeping positions when said elevator assembly occupiesa lower transpo'rting position, and adapted to carry said broom assemblyabove transporting position in response to lifting of said elevatorassembly from transporting position; force applying means connected tosaid vehicle and operatively associated with said elevator assembly forlifting said elevator assembly upwardly from said transporting positionout of the discharge path of refuse falling from said discharge openingwhereby said broom assembly is concurrently lifted upwardly abovetransportingl position and out of said discharge path; latching meansfor releasably holding said gate in closed position; and meansinterconnecting said latching means and said elevator assembly torelease said latching means in response to lifting of said elevatorassembly whereby said discharge path is unobstructed by said elevatorassembly and said broom assembly upon opening of said gate.

7. In a street sweeper vehicle having a refuse receiving hopper, a dumpgate spaced rearwardly of the supporting wheels of said vehicle forclosing a discharge opening formed in said hopper, a verticallyswingable pick-up broom assembly at the rear end of said vehicle, and anelevator assembly pivotally mounted on said hopper and positionedbetween said broom and said hopper to conduct refuse fro'm said broomupwardly into said hopper, the improvement comprising the combinationof: means interconnecting said broom assembly and said elevator assemblyfor limiting independent movement of said broom assembly between asweeping position and a transporting position of said broom assembly; afluid actuated plunger adapted to be remotely controlled by the operatorof said vehicle and drivingly connected to said first mentioned means toselectively move said broom assembly between sweeping and transportingpositions; a fluid actuated plunger4 adapted to be remotely controlledby the operator of said vehicle and operatively interconnected betweensaid vehicle and said elevator assembly to lift said elevator assemblyupwardly from a lowered transporting position and out of the dischargepath of refuse falling from said discharge opening whereby said broomassembly is concurrently lifted above transporting position and out ofsaid discharge path; latching means for releasably holding said gate inclosed position; and means interconnecting said latching means and saidelevator assembly to release said latching means in response to liftingof said elevator assembly whereby said discharge path is unobstructed bysaid elevator assembly and said broom assembly upon opening of saidgate.

8. In a street sweeper vehicle having a refuse receiving hopper, a dumpgate spaced rearwardly of the supporting wheels of said vehicle forclosing a discharge opening formed in said hopper and openable in adirection away from said hopper, a vertically swingable pick-up broom-assembly at the rear end of said vehicle, and an elevator assemblypivotally mounted on said hopper and positioned between said broom andsaid hopper, the improvement comprising the combination of: forceapplying means interconnecting said broom assembly and said elevatorassembly that is operable to move said broom assembly betweentransporting and sweeping positions when said elevator assembly occupiesa lower/ed transporting position and adapted to carry said broomassembly above transporting position in response to lifting of saidelevator assembly from transporting position; force applying meansconnected to said vehicle and operatively associated With said elevatorassembly for lifting said elevator assembly upwardly from saidtransporting position and out `of the discharge path of refuse fallingfrom said discharge opening whereby said broom assembly is concurrentlylifted upwardly above transporting position and out of said dischargepath; self-latching means including cooperating parts mounted on saidgate and on said hopper for holding said gate in closed position; andrigid means interconnecting the part of said latching means mounted onsaid gate and said elevator assembly and adapted to release saidlatching means in response to lifting of said elevator assembly and toopen said gate concurrently with lifting of said elevator assemblywhereby refuse is discharged through said discharge opening in a pathunobstructed by said elevator assembly and by said broom assembly.

9. In a street sweeper vehicle the combination of: a body assemblyincluding a rigidly mounted substantially enclosed refuse receivinghopper with an upper intake opening and a lower discharge opening formedin the rear end of said body assembly, said discharge opening beingspaced rearwardly of the `rear supporting wheels of said vehicle; abroom assembly comprising a pair of broom supporting arms pivotallyconnected at their forward ends to said vehicle and extending rearwardlyto support a pick-up broom behind said vehicle; an elevator assemblyincluding a housing that opens at its upper end into communication withsaid intake opening and receiving said broom in a lower end openingthereof, said housing supporting a means to convey refuse from saidbroom to said intake opening and being pivotally connected to saidhopper for vtelescoping angular movement into said intake opening; meansinterconnecting said broom assembly and said elevator assembly forlimiting independent movement of said broom assembly between a sweepingposition and a transporting position of said broom assembly; a fluidactuated plunger adapted to be remotely controlled by the operator ofsaid vehicle and drivingly connected to said means interconnecting saidassemblies to selectively move said broom assembly between sweeping `andtransporting positions; a fluid actuated plunger adapted to be remotelycontrolled by the operator of said vehicle and operativelyinterconnected between said vehicle hopper and said elevator assembly tolift said elevator assembly upwardly from a lowered transportingposition and out of the discharge path of refuse falling from saiddischarge opening whereby said broom assembly is concurrently liftedabove transporting position and out of said discharge path; a dump gateon said hopper for said discharge opening and openable in the directionof said elevator housing to release refuse from said hopper;self-latching means for normally hold-z ing said gate in closedposition; and means interconnecting said latching means and saidelevator assembly and adapted to release said latching means in responseto lifting of said elevator assembly to open said gate whereby refuse isdischarged through said discharge opening in a path unobstructed by saidelevator assembly and by said broom assembly.

References Cited in the le of this patent UNTTED STATES PATENTS 518,716Downs Apr. 24, 1894 1,224,771 Miller May 1, 1917 1,750,829 Wilson Mar.18, 1930 2,199,703 Hough May 7, 1940 2,286,245 Wilson et al June 16,1942 2,314,381 Arnett Mar. 23, 1943 2,316,826 Wachter Apr. 20, 19432,505,199 Mott Apr. 25, 1950 2,530,720 Paulson Nov. 21, 1950 2,708,280Autos et a1 May 17, 1955

